Treatment-related adverse events as predictive biomarkers of efficacy in patients with advanced neuroendocrine tumors treated with surufatinib: results from two phase III studies

Background

No validated biomarkers currently exist for predicting the efficacy outcomes in patients with neuroendocrine tumors (NETs) treated with antiangiogenic therapy. We aimed to evaluate the association between treatment-related adverse events (TRAEs) and efficacy outcomes of surufatinib in patients with advanced NET.

Patients and methods

We included patients with NET treated with surufatinib in two multicenter, randomized, double-blind, placebo-controlled, phase III trials (SANET-p and SANET-ep) in this study. The main exposure was the presence of any of the TRAEs including hypertension, proteinuria, and hemorrhage in the first 4 weeks of surufatinib treatment. The primary outcome of the study was investigator-assessed progression-free survival (PFS). PFS outcomes were estimated using the Kaplan–Meier method with the log-rank test. Hazard ratios (HRs) were calculated by using univariable and multivariable Cox proportional hazard regression models. Blinded independent image review committee (BIIRC) assessments and 4-week landmark analysis were also performed as supportive evaluations.

Results

During the study period, a total of 242 patients treated with surufatinib were included in the analysis, and 164 (68%) patients had at least one of hypertension, proteinuria, and hemorrhage in the first 4 weeks of treatment. The presence of TRAEs in the first 4 weeks was associated with prolonged median PFS [11.1 versus 9.2 months; HR 0.67, 95% confidence interval (CI) 0.47-0.97; P = 0.036]. In multivariable Cox regression analysis, the presence of TRAEs was also significantly associated with longer PFS (HR 0.65, 95% CI 0.44-0.97; P = 0.035). Similar results were obtained in the BIIRC assessments and 4-week landmark analysis.

Conclusions

Treatment-related hypertension, proteinuria, and hemorrhage could be potential biomarkers to predict antitumor efficacy of surufatinib in patients with advanced NET. Future prospective studies are needed to validate the findings.

Trial registration

ClinicalTrials.govNCT02589821; https://clinicaltrials.gov/ct2/show/NCT02589821 and ClinicalTrials.gov NCT02588170; https://clinicaltrials.gov/ct2/show/NCT02588170

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Treatment-related hypertension, proteinuria, or hemorrhage is associated with longer survival in NETs.

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The association is confirmed by the BIIRC assessments and 4-week landmark analysis.

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TRAEs can be biomarkers to predict antitumor efficacy in patients with NET.

Scrutinizing high-risk patients from ASC-US cytology via a deep learning model

BACKGROUND

Atypical squamous cells of undetermined significance (ASC-US) is the most frequent but ambiguous abnormal Papanicolaou (Pap) interpretation and is generally triaged by high-risk human papillomavirus (hrHPV) testing before colposcopy. This study aimed to evaluate the performance of an artificial intelligence (AI)-based triage system to predict ASC-US cytology for cervical intraepithelial neoplasia 2+ lesions (CIN2+).

METHODS

More than 60,000 images were used to train this proposed deep learning-based ASC-US triage system, where both cell-level and slide-level information were extracted. In total, 1967 consecutive ASC-US Paps from 2017 to 2019 were included in this study. Histological follow-ups were retrieved to compare the triage performance between the AI system and hrHPV in 622 patients with simultaneous hrHPV testing.

RESULTS

In the triage of women with ASC-US cytology for CIN2+, our system attained equivalent sensitivity (92.9%; 95% confidence interval [CI], 75.0%-98.8%) and higher specificity (49.7%; 95% CI, 45.6%-53.8%) than hrHPV testing (sensitivity: 89.3%; 95% CI, 70.6%-97.2%; specificity: 34.3%; 95% CI, 30.6%-38.3%) without requiring additional patient examination or testing. Additionally, the independence of this system from hrHPV testing (κ = 0.138) indicated that these 2 different methods could be used to triage ASC-US as an alternative way.

CONCLUSION

This de novo deep learning-based system can triage ASC-US cytology for CIN2+ with a performance superior to hrHPV testing and without incurring additional expenses.

Genetic analyses of blood β-hydroxybutyrate predicted from milk infrared spectra and its association with longevity and female reproductive traits in Holstein cattle

Ketosis is one of the most prevalent and complex metabolic disorders in high-producing dairy cows and usually detected through analyses of β-hydroxybutyrate (BHB) concentration in blood. Our main objectives were to evaluate genetic parameters for blood BHB predicted based on Fourier-transform mid-infrared spectra from 5 to 305 d in milk, and estimate the genetic relationships of blood BHB with 7 reproduction traits and 6 longevity traits in Holstein cattle. Predicted blood BHB records of 11,609 Holstein cows (after quality control) were collected from 2016 to 2019 and used to derive 4 traits based on parity number, including predicted blood BHB in all parities (BHBp), parity 1 (BHB1), parity 2 (BHB2), and parity 3+ (BHB3). Single- and multitrait repeatability models were used for estimating genetic parameters for the 4 BHB traits. Random regression test-day models implemented via Bayesian inference were used to evaluate the daily genetic feature of BHB variability. In addition, genetic correlations were calculated for the 4 BHB traits with reproduction and longevity traits. The heritability estimates of BHBp, BHB1, BHB2, and BHB3 ranged from 0.100 ± 0.026 (± standard error) to 0.131 ± 0.023. The BHB in parities 1 to 3+ were highly genetically correlated and ranged from 0.788 (BHB1 and BHB2) to 0.911 (BHB1 and BHB3). The daily heritability of BHBp ranged from 0.069 to 0.195, higher for the early and lower for the later lactation periods. A similar trend was observed for BHB1, BHB2, and BHB3. There are low direct genetic correlations between BHBp and selected reproductive performance and longevity traits, which ranged from -0.168 ± 0.019 (BHBp and production life) to 0.157 ± 0.019 (BHBp and age at first calving) for the early lactation stage (5 to 65 d). These direct genetic correlations indicate that cows with higher BHBp (greater likelihood of having ketosis) in blood usually have shorter production life (-0.168 ± 0.019). Cows with higher fertility and postpartum recovery, such as younger age at first calving (0.157 ± 0.019) and shorter interval from calving to first insemination in heifer (0.111 ± 0.006), usually have lower BHB concentration in the blood. Furthermore, the direct genetic correlations change across parity and lactation stage. In general, our results suggest that selection for lower predicted BHB in early lactation could be an efficient strategy for reducing the incidence of ketosis as well as indirectly improving reproductive and longevity performance in Holstein cattle.

CBETA: First Multipass Superconducting Linear Accelerator with Energy Recovery

Energy recovery has been achieved in a multipass linear accelerator, demonstrating a technology for more compact particle accelerators operating at higher currents and reduced energy consumption. Energy delivered to the beam during the first four passes through the accelerating structure was recovered during four subsequent decelerating passes. High-energy efficiency was achieved by the use of superconducting accelerating cavities and permanent magnets. The fixed-field alternating-gradient optical system used for the return loop successfully transported electron bunches of 42, 78, 114, and 150 MeV in a common vacuum chamber. This new kind of accelerator, an eight-pass energy recovery linac, has the potential to accelerate much higher current than existing linear accelerators while maintaining small beam dimensions and consuming much less energy per electron.

Cefazolin sodium pentahydrate combined with vacuum sealing drainage in the treatment of open fracture complicated with soft tissue injury

OBJECTIVE

To investigate the clinical efficacy of cefazolin sodium pentahydrate combined with vacuum sealing drainage (VSD) in the treatment of open fracture complicated with soft tissue injury.

METHODS

Sixty-three patients with open fracture complicated with soft tissue injury were divided into observation (n = 33) and control (n = 30) groups. After surgical reduction, fixation, and repair of the fractures, the control group was treated with VSD for 10 days, and the observation group was treated with cefazolin sodium pentahydrate based on VSD for 10 days. The infection control time was recorded. After treatment, the pain of patients was evaluated. Before and after treatment, the serum levels of C-reactive protein (CRP), interleukin (IL)-6, IL-8, tumor necrosis factor α (TNF-α), cortisol, epinephrine, norepinephrine, and glucose were detected. After 6 months of treatment, the total effective rate of the treatment was evaluated.

RESULTS

The infection control time and Visual Analogue Scale score after treatment in the observation group were significantly lower than in the control group, respectively (P < 0.05). After the treatment, the serum levels of CRP, IL-6, IL-8, TNF-α, cortisol, epinephrine, norepinephrine, and glucose in each group were significantly lower than before the treatment (P < 0.05), and each index in observation was significantly lower than in the control group (P < 0.05).

CONCLUSIONS

In the treatment of open fractures complicated with soft tissue injury, cefazolin sodium pentahydrate combined with VSD can effectively reduce inflammation and stress, thus improving the treatment efficacy.

RECENT ADVANCES IN STUDYING TANNIC ACID AND ITS INTERACTION WITH PROTEINS AND POLYSACCHARIDES

The purpose of this review was to gain a deeper understanding of tannic acid (TA) and its properties, which could be important for improving the technology of gluten-free food. TA is widely used in agriculture, food, medicine, and other fields due to its unique physiological functions (anti-tumor, anti-oxidation, antibacterial, anti-viral, etc.). It can closely interact with proteins and polysaccharides, which can significantly influence the structure, function, and nutritional properties of compounds. In this article, TA is chosen as a polyphenol model, and the structure of tannins and the degree of their extraction have been considered systematically. Prospective application of interaction between TA and common biological macromolecules have been presented. In this review, different classes of tannins are summarized. Advantages and disadvantages of different methods of extracting tannins have also been described. This review provides detailed information about the mechanisms of interaction of TA with biological macromolecules such as proteins and polysaccharides. Maize, buckwheat, rice flour and starch should be introduced as non-traditional raw materials in production of pasta for people ill with coeliac disease. Pasta dough from unconventional raw materials has non-standard rheological characteristics, and it is difficult to impart good plastic properties to it. That is why, studying the properties of tannins is necessary to improve the technology of gluten-free pasta. However, due to the different nature and composition of proteins, gluten-free foods do not have a network structure. So, they can hold neither water nor starch granules, their prepared dough is loose, with low viscosity, and is not easily moulded. That is why, the use of tannin to form a strong structure when developing a gluten-free pasta technology has become the main purpose of the research. Some potential problems of gluten-free dough processing can be solved by using new technical means. In view of this, the authors put forward the idea of using TА to form cross-links and a strong gluten-free dough structure.

Validation of a nomogram to predict the risk of cancer in patients with intraductal papillary mucinous neoplasm and main duct dilatation of 10 mm or less

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN) is premalignant pancreatic lesion. International guidelines offer limited predictors of individual risk. A nomogram to predict individual IPMN malignancy risk was released, with good diagnostic performance based on a large cohort of Asian patients with IPMN. The present study validated a nomogram to predict malignancy risk and invasiveness of IPMN using both Eastern and Western cohorts.

METHODS

Clinicopathological and radiological data from patients who underwent pancreatic resection for IPMN at four centres each in Eastern and Western countries were collected. After excluding patients with missing data for at least one malignancy predictor in the nomogram (main pancreatic duct diameter, cyst size, presence of mural nodule, serum carcinoembryonic antigen and carbohydrate antigen (CA) 19-9 levels, and age).

RESULTS

In total, data from 393 patients who fit the criteria were analysed, of whom 265 were from Eastern and 128 from Western institutions. Although mean age, sex, log value of serum CA19-9 level, tumour location, main duct diameter, cyst size and presence of mural nodule differed between the Korean/Japanese, Eastern and Western cohorts, rates of malignancy and invasive cancer did not differ significantly. Areas under the receiver operating characteristic (ROC) curve values for the nomogram predicting malignancy were 0·745 for Eastern, 0·856 for Western and 0·776 for combined cohorts; respective values for the nomogram predicting invasiveness were 0·736, 0·891 and 0·788.

CONCLUSIONS

External validation of the nomogram showed good performance in predicting cancer in both Eastern and Western patients with IPMN lesions.

A comparison of time-homogeneous Markov chain and Markov process multi-state models

Time-homogeneous Markov models are widely used tools for analyzing longitudinal data about the progression of a chronic disease over time. There are advantages to modeling the true disease progression as a discrete time stationary Markov chain. However, one limitation of this method is its inability to handle uneven follow-up assessments or skipped visits. A continuous time version of a homogeneous Markov process multi-state model could be an alternative approach. In this article, we conduct comparisons of these two methods for unevenly spaced observations. Simulations compare the performance of the two methods and two applications illustrate the results.

Multi-state models and missing covariate data: Expectation-Maximization algorithm for likelihood estimation

Multi-state models have been widely used to analyze longitudinal event history data obtained in medical and epidemiological studies. The tools and methods developed recently in this area require completely observed data. However, missing data within variables of interest is very common in practice, and it has been an issue in applications. We propose a type of EM algorithm, which handles missingness within multiple binary covariates efficiently, for multi-state model applications. Simulation studies show that the EM algorithm performs well for both missing completely at random (MCAR) and missing at random (MAR) covariate data. We apply the method to a longitudinal aging and cognition study dataset, the Klamath Exceptional Aging Project (KEAP), whose data were collected at Oregon Health & Science University and integrated into the Statistical Models of Aging and Risk of Transition (SMART) database at the University of Kentucky.

Spin-polarized charge trapping cell based on a topological insulator quantum dot

We demonstrate theoretically that a topological insulator quantum dot can be formed via double topological insulator constrictions (TICs), and can be used as a charge and/or spin carrier trap memory element.

Aβ vaccination in combination with behavioral enrichment in aged beagles: effects on cognition, Aβ, and microhemorrhages

Beta-amyloid (Aβ) immunotherapy is a promising intervention to slow Alzheimer's disease. Aging dogs naturally accumulate Aβ and show cognitive decline. An active vaccine against fibrillar Aβ 1-42 (VAC) in aged beagles resulted in maintenance but not improvement of cognition along with reduced brain Aβ. Behavioral enrichment (ENR) led to cognitive benefits but no reduction in Aβ. We hypothesized cognitive outcomes could be improved by combining VAC with ENR in aged dogs. Aged dogs (11-12 years) were placed into 4 groups: (1) control/control (C/C); (2) control/VAC (C/V); (3) ENR/control (E/C); and (4) ENR/VAC (E/V) and treated for 20 months. VAC decreased brain Aβ, pyroglutamate Aβ, increased cerebrospinal fluid Aβ 42 and brain-derived neurotrophic factor RNA levels but also increased microhemorrhages. ENR reduced brain Aβ and prevented microhemorrhages. The combination treatment resulted in a significant maintenance of learning over time, reduced Aβ, and increased brain-derived neurotrophic factor mRNA despite increased microhemorrhages; however, there were no benefits to memory. These results suggest that the combination of immunotherapy with behavioral enrichment leads to cognitive maintenance associated with reduced neuropathology that may benefit people with Alzheimer's disease.

Adaptive Trajectory Tracking Control using Reinforcement Learning for Quadrotor

Inaccurate system parameters and unpredicted external disturbances affect the performance of non-linear controllers. In this paper, a new adaptive control algorithm under the reinforcement framework is proposed to stabilize a quadrotor helicopter. Based on a command-filtered non-linear control algorithm, adaptive elements are added and learned by policy-search methods. To predict the inaccurate system parameters, a new kernel-based regression learning method is provided. In addition, Policy learning by Weighting Exploration with the Returns (PoWER) and Return Weighted Regression (RWR) are utilized to learn the appropriate parameters for adaptive elements in order to cancel the effect of external disturbance. Furthermore, numerical simulations under several conditions are performed, and the ability of adaptive trajectory-tracking control with reinforcement learning are demonstrated.

A mechanism of mesh-related post-herniorrhaphy neuralgia

PURPOSE

The objective is to compare nerve densities in explanted polypropylene meshes in patients with or without chronic pain. Pain has supplanted recurrences as a complication of hernia surgery. The increased incidence of pain mirrors a parallel increase in the use of polypropylene meshes. Neither triple neurectomy nor careful nerve preservation has brought relief. Perhaps because we have forgotten that nerves, in response to some evolutionary mechanism, tend to regenerate, undergo changes imposed by prosthetic elements and architecture, mimicking entrapment and compartment syndromes.

METHODS

A total of 33 hernia meshes have been analyzed: 17 excised due to severe pain, two for combined pain and recurrence, 14 sampled during revision for recurrence without pain. Each mesh had standardized sampling for histology and the nerves were highlighted by S100 stain. Nerve densities were assessed within the mesh spaces and in tissue outside the mesh.

RESULTS

The density of nerves present in the standardized mesh samples of patients complaining of pain was much more elevated than in the mesh of those patients who had a recurrence but no pain. The difference was statistically significant (p < 0.001). Excluding two patients who had both pain and recurrence, the difference was even more marked (p < 0.0001).

CONCLUSIONS

Re-innervation and neo-innervation are known to take place following hernia repairs in indigenous tissue as well as through polypropylene meshes. However, when pain is an overriding issue dictating mesh explant, the degree of mesh innervation is significantly higher when compared to mesh excised for recurrence. That increase has been confirmed statistically.

The Statistical Modeling of Aging and Risk of Transition Project: Data Collection and Harmonization Across 11 Longitudinal Cohort Studies of Aging, Cognition, and Dementia

Longitudinal cognitive trajectories and other factors associated with mixed neuropathologies (such as Alzheimer's disease with co-occurring cerebrovascular disease) remain incompletely understood, despite being the rule and not the exception in older populations. The Statistical Modeling of Aging and Risk of Transition study (SMART) is a consortium of 11 different high-quality longitudinal studies of aging and cognition (N=11,541 participants) established for the purpose of characterizing risk and protective factors associated with subtypes of age-associated mixed neuropathologies (N=3,001 autopsies). While brain donation was not required for participation in all SMART cohorts, most achieved substantial autopsy rates (i.e., > 50%). Moreover, the studies comprising SMART have large numbers of participants who were followed from intact cognition and transitioned to cognitive impairment and dementia, as well as participants who remained cognitively intact until death. These data provide an exciting opportunity to apply sophisticated statistical methods, like Markov processes, that require large, well-characterized samples. Thus, SMART will serve as an important resource for the field of mixed dementia epidemiology and neuropathology.

Transarterial chemoembolization for patients with unresectable hepatocellular carcinoma: a retrospective study of a 5-year experience in a single institution

BACKGROUND/AIMS

Transarterial chemoembolization (TACE) is the mainstay of management for patients with unresectable hepatocellular carcinoma (HCC). The aim of this study is to evaluate the survival rates of patients with unresectable HCC following TACE performed in a single center.

METHODOLOGY

The authors retrospectively assessed the electronic medical records of 512 patients in whom HCC was newly diagnosed from January 2008 to December 2012 at a single tertiary medical center. Patients with decompensated hepatic function were excluded. Hepatic artery infusion chemotherapy was performed using one drug or combinations of oxaliplatin, fluorouracil and doxorubicin. The primary endpoint of the study was overall survival (OS). Survival rates were calculated using Kaplan-Meier method.

RESULTS

A total of 512 HCC patients (425 men and 87 women; mean age, 58.9 years; age range, 38.3-86.1 years) were treated with TACE in a single center. The overall survival rates at 1, 2, and 3 years were 62%, 43%, and 37%, respectively. The overall median survival time from the start of TACE treatment was 15 months.

CONCLUSIONS

TACE is an effective minimally invasive therapy option for palliative treatment of HCC patients.

Chaperone-dependent Neurodegeneration: A Molecular Perspective on Therapeutic Intervention

Maintenance of cellular homeostasis is regulated by the molecular chaperones. Under pathogenic conditions, aberrant proteins are triaged by the chaperone network. These aberrant proteins, known as "clients," have major roles in the pathogenesis of numerous neurological disorders, including tau in Alzheimer's disease, α-synuclein and LRRK2 in Parkinson's disease, SOD-1, TDP-43 and FUS in amyotrophic lateral sclerosis, and polyQ-expanded proteins such as huntingtin in Huntington's disease. Recent work has demonstrated that the use of chemical compounds which inhibit the activity of molecular chaperones subsequently alter the fate of aberrant clients. Inhibition of Hsp90 and Hsc70, two major molecular chaperones, has led to a greater understanding of how chaperone triage decisions are made and how perturbing the chaperone system can promote clearance of these pathogenic clients. Described here are major pathways and components of several prominent neurological disorders. Also discussed is how treatment with chaperone inhibitors, predominately Hsp90 inhibitors which are selective for a diseased state, can relieve the burden of aberrant client signaling in these neurological disorders.

The effect of dornase alfa on ventilation inhomogeneity in patients with cystic fibrosis

Outcome measures to assess therapeutic interventions in cystic fibrosis (CF) patients with mild lung disease are lacking. Our aim was to determine if the lung clearance index (LCI) can detect a treatment response to dornase alfa in paediatric CF patients with normal spirometry. CF patients between 6-18 yrs of age with FEV(1 )≥ 80% pred were eligible. In a crossover design, 17 patients received 4 weeks of dornase alfa and placebo in a randomised sequence separated by a 4-week washout period. The primary end-point was the change in LCI from dornase alfa versus placebo. A mixed model approach incorporating period-dependent baselines was used. The mean ± sd age was 10.32 ± 3.35 yrs. Dornase alfa improved LCI versus placebo (0.90 ± 1.44; p = 0.022). Forced expiratory flow at 25-75% expired volume measured by % pred and z-scores also improved in subjects on dornase alfa (6.1% ± 10.34%; p = 0.03 and 0.28 ± 0.46 z-score; p = 0.03). Dornase alfa significantly improved LCI. Therefore the LCI may be a suitable tool to assess early intervention strategies in this patient population.

Carotid atherosclerosis and a reduced likelihood for lowered cognitive performance in a Canadian First Nations population

BACKGROUND

We investigated the associations among cardiovascular risk factors, carotid atherosclerosis and cognitive function in a Canadian First Nations population.

METHODS

Individuals aged > or = 18 years, without stroke, nonpregnant and with First Nations status were assessed by the Trail Making Test Parts A and B. Results were combined into a Trail Making Test executive function score (TMT-exec). Doppler ultrasonography assessed carotid stenosis and plaque volume. Anthropometric, vascular and metabolic risk factors were assessed by interview, clinical examinations and blood tests.

RESULTS

For 190 individuals with TMT-exec scores, the median age of the population was 39 years. Compared to the reference group, individuals with elevated levels of left carotid stenosis (LCS) and total carotid stenosis (TCS) were less likely to demonstrate lowered cognitive performance [LCS, odds ratio (OR): 0.47, 95% confidence interval (CI): 0.24-0.96; TCS, OR: 0.40, 95% CI: 0.20-0.80]. No effect was shown for plaque volume. In structural equation modeling, we found that for every 1-unit change in the anthropometric factor in kg/m(2), there was a 0.86-fold decrease in the percent of TCS (p < 0.05).

CONCLUSIONS

Individuals with elevated levels of LCS and TCS were less likely to demonstrate lowered performance. There was some suggestion that TCS mediates the effect of anthropometric risk factors on cognitive function.

Therapeutic vaccination against advanced pancreatic cancer by autologous dendritic cells pulsed with a MUC1 peptide: Preclinical results of a clinical phase I trial

e15652

Background: Pancreatic ductal adenocarcinoma has a particularly poor prognosis. Therefore, novel therapeutic strategies such as immunotherapy are required. The aim of the present phase I study was to evaluate the safety, immune responses and clinical activity of a vaccine based on autologous dendritic cells (DC) pulsed with a specific MUC1 peptide in advanced pancreatic cancer patients. Methods: Five patients who had pancreatic cancer ductal adenocarcinoma expressing MUC1 in stage of III/IV were enrolled to the clinical trial. Patients underwent leukapheresis to generate dendritic cells by culture in vitro with granulocyte macrophage colony-stimulating factor and interleukin-4 for 5 days. Dendritic cells were then pulsed overnight with MUC1 peptide (GVTSAPDTRPAPGSTAPPAH) and harvested for vaccination. Dendritic cells (3×106-6×106) were injected intradermally every 2 weeks for 3–4 times. Results: All patients remained with progressive disease. Four patients developed strong T-cell IFN-γ and Granzyme B Elispot responses to the vaccine. Most interestingly, the patient who was treated with the highest number of DC(6×106) had more number of CTL than other patients and showed delayed-type hypersensitivity responses at injection sites and this patient stopped application of the analgetics. Another patient with relapsed pancreatic cancer who had finished the 4 times of vaccination and then followed 6 times of chemotherapy with Gemcitabine had a surprisingly long term of survival of 12 month. No evidence of significant treatment related toxicity or auto-immunity was observed. Conclusions: This study showed the safety and clinical response of MUC1 peptide-pulsed dendritic cell therapy for patients with advanced pancreatic cancer. It confirms the capability of this DC vaccine to stimulate an immune response in patients with pancreatic cancer even in the presence of a large tumor burden. Dendritic cell therapy is recommended for further clinical studies in pancreatic cancer patients.

No significant financial relationships to disclose.

A novel recombinant tandem repeat DNA vaccine targeting at MUC1

3066

Background: Tandem repeat (TR) is the key epitope of mucin 1 (MUC1) for inducing cytotoxic T lymphocytes (CTL) to kill the tumor cells specifically. A novel recombinant TR DNA vaccine was constructed to study its induced immune responses. Methods: A recombinant human TR (rhTR) gene encoding a single TR polypeptide of MUC1 was synthesized and cloned into the multiple cloning sites of plasmid pcDNA3.1/Myc-his (+) A to construct the recombinant plasmid pcDNA3.1-TR/Myc-his (+) A (pTR plasmid). Expression of pTR plasmid was confirmed by transfection assay and Western blot analysis. C57BL/6 (H-2b) mice were immunized with pTR plasmid (n=15) by tibial muscle injection. Mice inoculated with the empty vector (EV group, n=15) and 0.9% NaCl solution (NS group, n=15) were used as vector and blank control respectively. Four weeks later, all mice were immunized again. Specific antibody detection and cytotoxic assay were used to evaluate the vaccine-induced TR specific immune responses. Results: DNA sequencing confirmed that the pTR plasmid was exactly constructed. Transfection assay and Western blot analysis found that the transfected COS7 cells expressed TR polypeptide of MUC1 48 hours after transfection. Cytotoxic assay showed that immunization with pTR plasmid into C57BL/6 mice resulted in more efficient induction of CTL specific cytolysis against TR polypeptide than that of EV group and NS group (p<0.01). Vaccine immunized mice had a higher equivalent concentration of anti-TR specific antibodies (2324μg/ml±238μg/ml) than that of EV group (1896μg/ml±533μg/ml, p<0.01) and NS group (1736μg/ml±142μg/ml, p<0.01). Conclusions: The novel recombinant TR DNA vaccine targeting at MUC1 was exactly constructed, immunization with which could induce TR specific CTL response and antibodies response in mice.

No significant financial relationships to disclose.

[Studies on the feasibility of detecting circulating antibodies in saliva of Schistosoma japonicum infected rabbits]

AIM

To investigate the feasibility of detecting anti-Schistosoma japonicum antibodies in saliva.

METHODS

Saliva and serum samples of 5 infected, 7 reinfected and 8 treated rabbits were collected at different times periods. The CAb in saliva and serum was detected by using ELISA.

RESULTS

The sensitivity of ELISA was 94.7% for saliva and 100% for serum. The specificity of ELISA was 100% for both saliva and serum.

CONCLUSION

Saliva can be used to detect circulating antibodies for the diagnosis of schistosomiasis japonica.

[Preparation of monoclonal antibodies by intrasplenic immunization of mice with urine circulating antigen from patients infected with Schistosoma japonicum]

AIM

To explore an efficient method for preparing monoclonal antibodies against circulating antigen of S. japonicum in the urine of schistosomiasis patients.

METHODS

The urine of schistosomasis patients were precipitated with 5% trichloroacetic acid, and then used to immunize the BALB/c mice by intrasplenic immunization to prepare McAb.

RESULTS

Two monoclonal cell lines against the CAg in the urine of schistosomiasis patients have been established. The immunoglobulin subclass of the 2 McAbs (2E6 and 2B11) were identified as IgM. The titres of 2E6 and 2B11 were 2.56 x 10(5) and 6.4 x 10(4). On immunodiffusion, McAb 2E6 showed one precipitation line with IHU-CAg, however, both McAbs did not react with NHU-CAg. Using ascitic fluid of 2B11 and 2E6 as capture antibody separately, and HRP-H11 as labelled antibody to detect the urine of 12 acute schistosomasis patients, 2B11 2E6 gave 6 and 3 positive, respectively, whereas 8 normal urine were all negative.

CONCLUSION

It is feasible to use CAg from schistosomasis patients' urine to prepare anti-CAg McAb by intrasplenic immunization in mice.

[Determination of circulating antigen in urine of rabbits infected with Schistosoma japonicum]

AIM

To develop an immunoassay for the detection of circulating schistosome antigen (CSA) in host urine.

METHODS

CSA extracted from the urine of the rabbits infected with Schistosoma japonicum was used for preparing and selecting specific monoclonal antibody. A one-step dot-ELISA using this specific McAb and a 2nd antibody was used for detection of circulating schistosome antigen in the urine of infected rabbits.

RESULTS

No CSA was detected in urine from all of 22 rabbits before infection. The positive rate of CSA in infected rabbits was correlated with the intensity of infection and the time of infection. No CSA was detected in the urine rabbits of 3 weeks after infection with 25 cercariae while the positive rate of CSA in the urine from rabbits infected with 200 cercariae was 40% and 100% after 3 and 6 weeks, respectively. A combination of CSA detection in both urine and serum may increase the detectability.

CONCLUSION

The specific McAb prepared by urine CSA of Schistosoma japonicum-infected rabbits can be used as a probe for detecting CSA in the urine of infected rabbits.

[Establishment and application of dipstick sandwich colloidal dye immunoassay for circulating antigen detection in schistosomiasis patients]

AIM

To set up a simple immunoassay for the detection of circulating antigens in host serum.

METHODS

A kind of colloidal pale purple dye (HFRL) used as a staining reagent for immunoassay was first selected from the dyes produced in China and an optimum condition for labelling the dye onto the combined IgM antibodies was explored. A dipstick sandwich colloidal dye immunoassay (DS-DIA) for the detection of circulating antigens in host sera was established.

RESULTS

The minimal concentration of SEA detected was 5 ng/ml by DS-DIA. Serum circulating antigen detection in 14 cases of acute schistosomiasis japonica, 113 chronic cases and in 113 healthy controls revealed that the sensitivity was 100% in acute cases, 52.2% in chronic cases and the specificity was 92.9% for uninfected students. The sensitivity and specificity of DIA were similar to those of dot-ELISA. A certain degree of diagnostic complementarity up to 76.1% in sera from these patients was seen when DS-DIA and dot-ELISA were used in paralle.

CONCLUSION

DS-DIA is a simple, economical and reliable method for detecting circulating antigens of Schistosoma japonicum, having a wide potential value especially for field use.

[Comparative observation on the efficacy of several test/probe systems for detecting schistosome circulating antigen]

AIM

To compare the efficacy of 5 test/probe systems for the detecting of schistosomal circulation antigen (SCA) in sera from infected rabbits.

METHODS

Nine rabbits were infected with monosexual cercariae (either male or female), 7 rabbits were infected with bisexual cercariae as controls. Blood samples were collected periodically post infection (p.i). 15 rabbits were infected each with 250 bisexual cercaria and divided into 3 groups, 2 groups were treated with allyl thiourea (295-590 mg/kg) from 19 d or 46 d respectively, to inhibit their egg formation. One untreated group was used as control. Blood samples were collected weekly until 8 wk post infection. SCA detecting methods include (1) dot-ELISA/McAb anti-surface membrane antigen of adult worms (8SE4), (2) dot-ELISA/McAb anti-CCA (3D10), (3) Sandwich dot-ELISA/McAb anti-egg antigen (MG2), (4) Sandwich-ELISA/McAb anti-egg antigen (2H10), (5) Sandwich-ELISA/McAb anti-CAA (1B10).

RESULTS

Using method (1) all of the 18 rabbits infected with monosexual cercariae were negative. Using method (2) only 1 rabbit harboured 133 male worms showed positive. Using method (5) no SCA were detected in sera from female cercariae-infected rabbits but 3 out of 9 male cercariae-infected rabbits showed positive reaction. SCA detecting results from rabbits treated with allyl thiourea: both method (1) and (3) showed negative in rabbits treated from 19 d (p.i.) but all gave positive reaction in 6-7 wk in rabbits treated from 46 d (p.i.). There were all negative detected by using method (4) and all positive at 6 wk (p.i.) detected by method (5) in rabbits of 3 groups whether treated or non-treated.

CONCLUSION

Various test/probe systems have different efficacy in detecting SCA but (5) of the methods (1)(2) tests/probe systems could not detect SCA in rabbits with single female cercariae infection. From the egg formation inhibition study, the SCA detected by McAb 8SE4 dot-ELISA might be related to egg maturation. Whether the surface membrane antigen of adult worm has common antigenic component with egg antigen remains to be studied.

Artificial neural network-based predictive model for bacterial growth in a simulated medium of modified-atmosphere-packed cooked meat products

The data of Devilieghere et al. (Int. J. Food Microbiol. 1999, 46, 57--70) on bacterial growth in a simulated medium of modified-atmosphere-packed cooked meat products was processed for estimating maximum specific growth rate mu(max) and lag phase lambda of Lactobacillus sake using artificial neural networks-based model (ANNM) computation. The comparison between ANNM and response surface methodology (RSM) model showed that the accuracy of ANNM prediction was higher than that of RSM. Two-dimensional and three-dimensional plots of the response surfaces revealed that the relationships of water activity a(w), temperature T, and dissolved CO(2) concentration with mu(max) and lambda were complicated, not just linear or second-order relations. Furthermore, it was possible to compute the sensitivity of the model outputs against each input parameter by using ANNM. The results showed that mu(max) was most sensitive to a(w), T, and dissolved CO(2) in this order; whereas lambda was sensitive to T the most, followed by a(w), and dissolved CO(2) concentrations.

[Study on the relation between the cell cycle regulators and laryngeal carcinogenesis]

OBJECTIVE

To investigate the clinicopathological significance of the Cyclin E, p21WAF1/CIP1 and p53 expression in laryngeal carcinogenesis.

METHOD

The expression of Cyclin E, p21WAF1/CIP1 and p53 was examined by using immunohistochemical method in normal epithelia (20), dysplastic epithelia (40) and laryngeal cancers (60).

RESULT

1. In normal epithelium, dysplastic squamous epithelium and in squamous cell carcinoma of the larynx, the positive immunostaining rate of Cyclin E protein was 5.0%(1/20), 20.0%(8/40) and 45.0%(27/60) respectively (P < 0.001), and p21WAF1/CIP1 protein was 95.0%(19/20), 75.0%(30/40) and 63.3%(38/60) respectively (P < 0.01), while the rate of p53 was 0, 30.0%(12/40) and 61.7%(37/60)(P < 0.001) respectively. 2. p21WAF1/CIP1 positive expression in highly, moderately and poorly differentiated carcinomas were 76.2%(16/21), 66.5%(19/29) and 30.0%(3/10) respectively (P < 0.05), p21WAF1/CIP1 protein expression was significantly associated with tumour cell differentiation. 3. The positive expression of Cyclin E closely related with the positive expression of p53 (P < 0.05). No correlation was found between p21WAF1/CIP1 expression and p53 expression.

CONCLUSION

1. Cyclin E and p53 could be an early molecular event in the carcinogenesis of larynx. 2. p21WAF1/CIP1 expression is associated with tumour cell differentiation. 3. The mutual mechanism of cell cycle regulators (Cyclin E, p21WAF1/CIP1 and p53) play an important role in the laryngeal carcinoma.

Physician-patient discussions of controversial cancer screening tests

BACKGROUND

Screening mammography for younger women and prostate-specific antigen (PSA) measurement have controversial benefits and known potential adverse consequences. While providing informed consent and eliciting patient preference have been advocated for these tests, little is known about how often these discussions take place or about barriers to these discussions.

METHODS

We administered a survey to medical house staff and attending physicians practicing primary care. The survey examined physicians' likelihood of discussing screening mammography and PSA testing, and factors influencing the frequency and quality of these discussions.

RESULTS

For the three scenarios, 16% to 34% of physicians stated that they do not discuss the screening tests. The likelihood of having a discussion was significantly associated with house staff physicians' belief that PSA screening is advantageous; house staff and attending physicians' intention to order a PSA test, and attending physicians' intention to order a mammogram; and a controversial indication for screening. The most commonly identified barriers to discussions were lack of time, the complexity of the topic, and a language barrier.

CONCLUSIONS

Physicians report they often do not discuss cancer screening tests with their patients. Our finding that physicians' beliefs and intention to order the tests, and extraneous factors such as time constraints and a language barrier, are associated with discussions indicates that some patients may be inappropriately denied the opportunity to choose whether to screen for breast and prostate cancer.

Phospholipase C is involved in kinetochore function in Saccharomyces cerevisiae

The budding yeast PLC1 gene encodes a homolog of the delta isoform of mammalian phosphoinositide-specific phospholipase C. Here, we present evidence that Plc1p associates with the kinetochore complex CBF3. This association is mediated through interactions with two established kinetochore proteins, Ndc10p and Cep3p. We show by chromatin immunoprecipitation experiments that Plc1p resides at centromeric loci in vivo. Deletion of PLC1, as well as plc1 mutations which abrogate the interaction of Plc1p with the CBF3 complex, results in a higher frequency of minichromosome loss, nocodazole sensitivity, and mitotic delay. Overexpression of Ndc10p suppresses the nocodazole sensitivity of plc1 mutants, implying that the association of Plc1p with CBF3 is important for optimal kinetochore function. Chromatin extracts from plc1Delta cells exhibit reduced microtubule binding to minichromosomes. These results suggest that Plc1p associates with kinetochores and regulates some aspect of kinetochore function and demonstrate an intranuclear function of phospholipase C in eukaryotic cells.

Expression and regulation of mRNAs for insulin-like growth factor-I receptor and LH receptor in corpora lutea

Relationship between insulin-like growth factor-I receptor (IGF-IR) and luteinizing hormone receptor (LHR) mRNA expression as well as their regulation was determined in rat corpora lutea (CL). In the CL of estrous cycle rat, LHR mRNA positive CL expressed high level of mRNA of IGF-IR. While the expression of LHR mRNA decreased on estrus, the CL still expressed relatively high level of IGF-IR mRNA. In pseudopregnant rat CL, the expression level of LHR mRNA was low on day 1, the most intense signals were detected on day 8, the signals of LHR mRNA became undetectable on day 14. In contrast to LHR expression, the high level of IGF-IR mRNA was observed in pseudopregnant CL of day 1, and thereafter its signals were detected from day 2 to day 14. Pregnant rat CL expressed both LHR and IGF-IR mRNAs. IGF-I stimulated LHR expression in CL. PGF(2alpha) inhibited expression of IGF-IR and LHR. PGE(2) negated the inhibiting effects of PGF(2alpha). These data suggest that IGF-I may be involved in regulating CL function, and maintaining CL structure through changes in expression of its receptors. Inhibited expression of IGF-IR by PGF(2alpha) may be part of mechanisms for regression of CL.

[The protective effects of cardiac ischemic preconditioning on lung in cardiac operation with cardiopulmonary bypass]

Twenty direct vision intracardial operation patients were divided into two groups randomly. After cardiopulmonary bypass, ten patients were treated with myocardial ischemic preconditioning. The aorta were clamped for 3 minutes and released for 3 minutes (Group IP). Another ten patients were not treated with ischemic preconditioning (Group C), only underwent 6 minutes cardiopulmonary bypass. Then the aorta were clamped and intracardial operation were done. The left atrium blood and lung tissue were collected just after thoractomy and half an hour after cardiac reperfusion in both groups.

RESULTS

(1) The numbers of polymorphonuclear (PMN) of the two groups were increased significantly after cardiopulmonary bypass (P < 0.01). (2) The number of PMN and SOD, PaO2 contents were significantly higher in Group IP than in Group C (P < 0.05). (3) The numbers of PMN in lung interstitum under microscopy were less in Group IP than in Group C. (4) MDA contents were less in Group IP than in Group C (P < 0.05). (5) Histological finding showed less damage in Group IP than in Group C. It is evident that cardiac ischemic preconditioning could protect lung against ischemia reperfusion injury. The possible mechanisms are that ischemic preconditioning inhibites the accumulation and activation of PMN in lung tissue and reduces the production of oxygen free radicals.

Inhibition of constitutively activated Stat3 signaling pathway suppresses growth of prostate cancer cells

Overexpression of interleukin 6, a downstream target of the GBX2 homeobox gene, has been linked to the progression of prostate cancer. The Janus kinase-signal transducers and activators of transcription signaling pathway transmits interleukin 6-mediated signals from cell surface receptors to the target genes in the nucleus and is critical in mediating cellular growth and differentiation. We demonstrate that cells derived from both rat and human prostate cancers have constitutively activated Stat3, with Stat3 activation being correlated with malignant potential. Blockade of activated Stat3 by ectopic expression of a dominant-negative Stat3 in human prostate cancer cells significantly suppresses their growth in vitro and their tumorigenicity in vivo. Furthermore, the Janus kinase inhibitor, tyrphostin AG490, inhibited the constitutive activation of Stat3 and suppressed the growth of human prostate cancer cells. These results indicate that activation of Stat3 signaling is essential in the progression of prostate cancer cells and suggest that targeting Stat3 signaling may yield a potential therapeutic intervention for prostate cancer.

Interleukin-6 induces prostate cancer cell growth accompanied by activation of stat3 signaling pathway

BACKGROUND

Interleukin-6 (IL-6) is a pleiotropic cytokine that regulates growth and differentiation of various types of malignant tumors, including prostate carcinomas. The levels of IL-6 are elevated in sera of patients with metastatic prostate cancer. In this study, we evaluate the role of IL-6 in the growth regulation of prostate cancer cells.

METHODS

Expression of IL-6 and its receptors in human prostate cancer cells was measured by ELISA and RT-PCR. The effects of IL-6 on cell growth were evaluated by ectopically expressing IL-6 cDNA into IL-6-negative LNCaP human prostate cancer cells. Stat3 DNA binding activities were analyzed by electromobility shift assay and supershift assay.

RESULTS

Expression of IL-6 was detected in the androgen-insensitive prostate cancer cell lines (i.e. , TSU, PC3, and DU145), but not in the androgen-sensitive LNCaP cell line. IL-6 receptors, including both IL-6-specific receptor alpha chain and gp130 signal transducer, are expressed in all human prostate cancer cell lines (i.e., LNCaP, TSU, PC3, and DU145). Overexpression of IL-6 by ectopically expressing IL-6 into IL-6-negative LNCaP human prostate cancer cells significantly increased clonogenic ability and cell proliferation in vitro compared to the IL-6-negative parental LNCaP cells and the antisense controls. This growth stimulation by IL-6 was accompanied by activation of the Stat3 signaling transduction pathway.

CONCLUSIONS

IL-6 is an autocrine growth factor for LNCaP human prostate cancer cells; the effects of IL-6 on prostate cancer cell growth are mediated through the Janus kinase-signal transducers and activators of transcription (JAK-STAT) signaling pathway.

Enhanced GBX2 expression stimulates growth of human prostate cancer cells via transcriptional up-regulation of the interleukin 6 gene

Previous studies demonstrated that the GBX2 homeobox gene is consistently overexpressed in cultured human prostate cancer cell lines. In this study, the human GBX2 cDNA was cloned and a quantitative reverse transcription-PCR method used to demonstrate that GBX2 mRNA expression is enhanced in approximately 70% of human prostate cancer tissues compared with normal human prostate tissues. Purified recombinant GBX2 protein binds specifically to an ATTA motif within the promoter of the interleukin 6 (IL-6) gene. Using an antisense approach, down-regulation of the expression of GBX2 correlated with decreased expression of IL-6 and an inhibition of tumorigenicity of PC3 human prostate cancer cells. In addition, in vitro growth of the antisense clones was partially restored by exogenous addition of recombinant IL-6 protein to the culture media. These data demonstrated that enhanced GBX2 expression results in a stimulation of malignant growth of prostate cancer cells and that part of this stimulation involves up-regulation in the transcription of the IL-6 gene.

Methylation of the CD44 metastasis suppressor gene in human prostate cancer

Previous studies demonstrated that CD44 is a metastasis suppressor gene for prostate cancer and that the expression of CD44 both at mRNA and protein levels is down-regulated during prostate cancer progression, with down-regulation being correlated with higher tumor grade, aneuploidy, and distant metastasis. In this study, we evaluated DNA hypermethylation as a potential mechanism accompanying this decreased CD44 expression in human prostate cancer. Nucleotide sequence analysis revealed a CpG island in the CD44 transcriptional regulatory region. We found that cytosine methylation of CD44 promoter occurs in CD44-negative prostate cancer cell line (i.e., LNCaP) but not in prostate cancer cell lines (i.e., TSU, PC3, and DU145) expressing this gene. In addition, we examined methylation status of CD44 in 84 matched normal and cancer prostate specimens. Hypermethylation of the 5' CpG island of CD44 gene was observed in 31 of 40 primary prostate cancer specimens, 3 of 4 distant organ site metastases obtained at autopsy from men who died of prostate cancer, and 4 of the 40 matched normal tissues. These results demonstrated that methylation of the 5' CpG island of CD44 gene is closely associated with transcriptional inactivation, resulting in a decreased expression of CD44 in human prostate cancer.

Suppression of the tumorigenicity of prostatic cancer cells by gene(s) located on human chromosome 19p13.1-13.2

BACKGROUND

In previous reports, we used microcell fusion-mediated chromosomal transfer to introduce normal human chromosomes into highly metastatic rat prostatic cancer cells to map the location of tumor and metastasis suppressor genes. The gene for prostate-specific antigen as well as several classes of genes, including cell adhesion molecules, previously demonstrated to be altered during prostate cancer progression, were mapped to human chromosome 19.

METHODS

A normal human chromosome 19 was introduced into Dunning-R3327 AT6.1 rat and TSU-prl human prostatic cancer cells by microcell-mediated chromosome transfer to test the suppressive effects of this chromosome on prostate cancer. Five independent hybrid clones from Dunning-R3327 AT6.1 rat prostatic cancer cells and four independent hybrid clones from TSU-pr1 human prostatic cancer cells were isolated, karyotyped, allelotyped, and analyzed for in vitro and in vivo growth characteristics.

RESULTS

Introduction of human chromosome 19 into both the rat and human prostatic cancer cells resulted in alteration of cell morphology in vitro and suppression of tumorigenicity in vivo in athymic nude mice. Highly polymorphic SSR2 markers mapped to human chromosome 19 were used to determine the portions of human chromosome 19 retained in the hybrids. These analyses identified a region localized on human chromosome 19p13.1-13.2 that is responsible for the tumor suppression of both rat and human prostatic cancer cells. The expression of several genes previously mapped to this human chromosome 19p13.1-13.2 region (i.e., ICAM-1, Notch3, and Stau) were analyzed to evaluate if they could be candidate suppressor genes for prostate cancer cell growth in vivo, but no expression patterns consistent with those predicted for a suppressor gene were observed.

CONCLUSIONS

Human chromosome 19p13.1-13.2 contains potential tumor suppressor gene(s) for prostate cancer.